1. Field of the Invention
This invention relates to an improvement in a control system for a combined weighing apparatus which includes a plurality of measuring hoppers supplied with products to be measured from transfer means for measuring weights of the products to select a weight equal to or near to a set weight from any combinations of the measured weights, and more particularly, to an improvement in a condition-setting system and a measuring hopper combination-selecting system.
2. Description of the Prior Art
In prior art combined weighing apparatuses, every time the kind of product to be measured changes, the set weight, a deviation value, an item is input into a system by the operation of keys, and transfer conditions (transfer time, transfer power and the like) to hoppers are newly set and adjusted. In changing products to be measured, therefore, the operation efficiency cannot be expected to be improved due to the these troublesome input operations and adjustment operations.
In prior art measuring hopper combination-selecting systems, moreover, after weights of products supplied into a plurality of measuring hoppers have been individually measured, the measured values are suitably combined to calculate all the combination weights, from which a weight nearest to a set weight is selected.
In combined weighing apparatuses, the higher the number of measuring hoppers, the higher is the measuring accuracy. If the measuring hoppers are many, however, the number of combinations is greatly increased. For example, the relation between the numbers of measuring hoppers and combinations are as follows.
8 measuring hoppers . . . 255 combinations PA1 10 measuring hoppers . . . 1,023 combinations PA1 16 measuring hoppers . . . 65,535 combinations
In the prior art combination arithmetic methods, if the measuring hoppers to be combined are more than 10, it takes a considerably long time to combine the measuring hoppers, lowering its operation efficiency.
Furthermore, even if a combined weight nearest to a set weight is found in a first part of the combination arithmetic operation, the combined weight is selected after the remaining combination arithmetic operation has been effected, so that precious time is uselessly lost.
Moreover, even if the combination weight nearest the set weight is selected, its accuracy is not necessarily high. For example, when the products in respective measuring hoppers are considerably unbalanced, even the combined weight nearest to the set weight is often remarkably different from the set weight.